Evolution by natural selection was an idea revealed to the world 150 years ago tomorrow, by two men, the famous Charles Darwin, and the not so famous Alfred Russel Wallace.
Wallace and Darwin both came up with biology's most important concept and their theory was presented to the Linnean Society in London on 1 July 1858.
The Natural History Museum is marking this anniversary with a small display of original objects that tell how Wallace and Darwin independently developed the same idea.
Original copies of the scientific article they presented in 1858 are on display, as well as objects such as a bird of paradise collected by Wallace and pigeon bones that were prepared by Darwin. The display shows the different ways these two men worked.
Scientists had been looking for an explanation of how and why there was such an amazing variety of life on Earth.
Alfred Russel Wallace
Wallace and Darwin explained this diversity through the idea that species evolve by a process called natural selection.
Natural selection is where the fittest individuals of a species are more likely to survive and reproduce and pass their advantageous characteristics to their offspring.
The idea of natural selection occurred to Wallace while he was suffering from a fever on a remote Indonesian island in February 1858.
Unknown to Wallace, Darwin had worked out the same theory about 20 years earlier, but hadn't published it yet.
In March 1858, Wallace sent his paper on natural selection to Darwin. Darwin's colleagues decided to present the two men's theory to a meeting of the Linnean Society on July 1st.
The society published Darwin and Wallace's ideas a month later and the theory of natural selection went on to change the way the world thought about biology.